Spectrum markets: Challenges
Ahead
MARTIN WEISS
SCHOOL OF INFORMATION SCIENCES
UNIVERSITY OF PITTSBURGH
[email protected]
General viewpoint
2
 Despite liberalization (e.g., Australia), why haven’t
spectrum markets become visible?
 Transaction costs matter


Liquidity
Enforcement
 Secondary user/entrant viewpoint is critical
 What are the application requirements?
QoS
 Spatial configuration


What are the alternatives?
 Focus has been on “naked spectrum”
Starting context
©Mark Hurst. Used with permission
3
Entrant’s context
4
 Choice parameters
 Exclusive or shared access?
 Permanent license via primary market (or administrative
assignment)?
 Dimensions of choice
Non-Cooperative
Cooperative
Primary
• WiFi
• License trading/
Secondary markets
Secondary
• Opportunistic use
• TV White Spaces
• UWB
• MVNO
• Secondary use
What are spectrum holes good for?
Temporal
5
Non-cooperative
Cooperative
Static
• Elastic & inelastic
• Elastic & inelastic
Periodic
• Elastic
• Inelastic w. extra
channel (maybe)
• Elastic
• Inelastic w. extra channel
(maybe)
Stochastic
• Elastic
• Inelastic
• QoS = f(spectrum
hole density)
• Elastic
• Inelastic
• QoS = f(price)
What types of market mechanisms are appropriate for
trading spectrum?
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 Spectrum access is a complex good/service
 What are valued attributes of a trading mechanism?
 Anonymization?
 Low transaction costs?
 Speed?
 Others?
 Alternatives
 Bi-lateral bargaining
 Brokerages
 Exchanges
What technical restrictions should be placed on
spectrum rights/users/service providers?
7
 Participants need mechanisms to support
 Transaction audits
 Execution enforcement
 Some standards might prove valuable
 Spectrum sharing protocols
 Negotiation protocols/channels
Will spot markets for spectrum exist in 10 years?
8
 Depends on
 Liquidity
 Transaction costs
Enforcement
 Trust


Transaction support
Exchange/brokers
 Clearing mechanisms
 Standard trading unit
 Price reporting

 Best chances in the near term
 Limited-scope opportunities
What role might spectrum sensing/cognitive radio play
in spectrum markets?
9
 Software radios are essential


Cost reduction is critical going forward
Wide tuning range is desirable, which is challenging for antenna and
RF front end design
 Sensing is hard and costly


You have to know what you’re looking for to find it
Cooperative sensing has density and correlation problems
 Secondary markets


Licenses are traded
Sensing is focused on enforcement
 Secondary use


Sensing may be useful if multiple secondary users share temporary
licenses
Enforcement
Questions?
10
http://www.webwhispers.org/news/apr2005.htm